BEIJING — Chen Guangcheng, the blind self-taught lawyer whose plight has been at the center of U.S.-China diplomacy in recent weeks, said Wednesday that he still has seen no progress on his request for a new passport and that U.S. diplomats continue to be barred from the Beijing hospital where he remains confined.

In a brief telephone interview Wednesday, Chen also said that he is still waiting for the Chinese government to keep a promise that he said it made to him to investigate and prosecute the local officials who had held him unlawfully in his farmhouse in Dongshigu village, in the eastern province of Shandong.

Chen said he expects to be allowed to leave the country for a time to study in the United States, according to the tentative deal reached by Chinese officials and U.S. diplomats during a visit here last week by Secretary of State Hillary Rodham Clinton. Chen said that the passports he and his wife hold have expired and that he has not been told whether they can be renewed. He said no Chinese officials have come to discuss the matter with him.

“Changing a passport should be easier than applying for a new one,” Chen said.

The activist also said that he has not seen any U.S. Embassy staff members since Friday. “I can’t say I’m not worried,” he said, but added: “I’m just letting nature take its course on whether I can go abroad. As long as things don’t move too slowly.”

Chen left the U.S. Embassy, where he took refuge after a dramatic April 22 flight from Shandong, a week ago. Since then, he has been confined to Beijing’s Chaoyang hospital, where he is being treated for broken bones in his foot, an injury he suffered while escaping. Police and plainclothes guards have blocked U.S. diplomats, friends, supporters and journalists from entering the hospital to see him, and his wife, Yuan Weijing, and their children have mostly been barred from leaving his room.

On Wednesday, Chen reported some small signs of progress. He said that since Monday, his children have been allowed to play in the hospital’s outdoor courtyard for half an hour each morning and afternoon. He said his wife “still has trouble going out, but she has made it,” noting that she has periodically been allowed outside to meet with U.S. diplomats. He has been permitted only one brief visit with the diplomats Friday, despite Chinese officials’ earlier assurances of regular access to him.

U.S. diplomats have been able to speak with Chen by phone. Journalists have been warned that they risk expulsion from China if they try to enter the hospital to see Chen.

Hospital authorities said Chen is under the control of security officials and is allowed no unauthorized visitors. Beijing police said requests to visit him should be taken up with “relevant authorities.”

Chen said he is still most worried about his relatives in Shandong, particularly his brother and his sister-in-law. “I haven’t talked to them for several days,” the activist said. He said he was able to speak to his mother after authorities in Linyi city installed a land line in her home.

Chen said he expected Beijing officials to make good on their pledge to investigate his unlawful detention. “There’s no news” on it, he said. “But this thing has been publicized. It will affect their credibility if they don’t start an investigation.”

He added, “If I didn’t believe them, I never would have left the U.S. Embassy.”